Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 910 · 40 questions

Remember (Find the topic, use the idea): Find the topic: circuit, safety, formula, component, program, sensor or IoT. Use that lesson’s rule — complete loop, V = I × R, P = V × I, last command wins, true → if part. Safety answers are always: low voltage, dry hands, an adult, never the mains.

1. 1.Which of these is measured in ohms (Ω)? (a) power (b) energy used each second (c) how much a part resists (d) the flow of charge
2. 2.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) by Wi-Fi (b) in parallel (c) in series (d) not joined
3. 3.🔋 7 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
4. 4.True or false: a siren mainly makes movement. (a) True (b) False
5. 5.🔁 count = 5
   repeat 3 times { count = count + 5 }
   What is count at the end?
6. 6.True or false: on an LED, the leg by the flat edge is the anode (+). (a) False (b) True
7. 7.⚙️ What is an actuator? (a) a battery (b) an output that acts (c) a program (d) a sensor
8. 8.True or false: “a temperature reading” is the input. (a) True (b) False
9. 9.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 8 LOW
   set pin 8 LOW
   set pin 8 LOW
   set pin 8 LOW
   Is the LED ON or OFF at the end? (a) OFF (b) ON
10. 10.🧾 A 50 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
11. 11.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the USB port (b) the main chip (c) the voltage regulator (d) the pins
12. 12.True or false: “compare with a limit” is the output. (a) False (b) True
13. 13.🔐 Privacy for a smart device means controlling … (a) its colour (b) its battery size (c) who can see your data (d) how loud it beeps
14. 14.🔍 Which is the odd one out? (a) stay away from pylons (b) dry your hands first (c) touch a switch when wet (d) build with an adult near
15. 15.⚡ A 6 W device works on 12 V. What current does it take (in amperes)? =
16. 16.Which of these is an insulator? (a) an iron nail (b) a plastic ruler (c) a copper wire (d) a steel coin
17. 17.🧩 Which part changes electrical energy into sound? (a) a resistor (b) a diode (c) a buzzer (d) a capacitor
18. 18.Which of these gives us electricity? (a) a refrigerator (b) a solar panel (c) an air conditioner (d) a washing machine
19. 19.🧮 A 13 V battery is joined to 8 Ω and 5 Ω resistors in series. What current flows (in amperes)? =
20. 20.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 250 ms }
    How many times does the LED blink in 6 seconds?
21. 21.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
22. 22.📏 How many kilowatts (kW) is 1950 W? =
23. 23.🧮 Resistors of 20 Ω and 33 Ω are joined in series. What is the total resistance (in ohms)?
24. 24.Which of these gives us electricity? (a) a mobile phone (b) a computer (c) a television (d) a wind turbine
25. 25.True or false: to share only needed data is a risky habit. (a) False (b) True
26. 26.🔋 A 12 V battery and one 1.5 V cell are joined in series, all facing the same way. What is the total voltage (in volts)? =
27. 27.🔍 Which is the odd one out? (a) iron one shirt at a time (b) set the AC to 24 °C (c) leave the TV on standby (d) run fans in empty rooms
28. 28.True or false: “a light level reading” is the input. (a) False (b) True
29. 29.🤖 Microcontroller or laptop: which one runs many apps at once? (a) laptop (b) microcontroller
30. 30.🔋 What should you do with used-up cells? (a) cut them open (b) bury them in soil (c) throw them in a fire (d) give them for recycling
31. 31.⚡ A device works on 5 V and takes 0.25 A. What is its power (in watts)? =
32. 32.🔘 Which kind of switch flips up or down? (a) a toggle switch (b) a push button (c) a reed switch (d) a tilt switch
33. 33.🔗 Series or parallel circuit: “one out, the rest glow”? (a) parallel (b) series
34. 34.Which of these is the output? (a) a motion sensor signal (b) an alert on the phone (c) check if temp > 30 (d) compare with a limit
35. 35.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an output (c) an input (d) a fuse
36. 36.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a rubber eraser. Does the bulb glow? (a) Yes (b) No
37. 37.🔋 5 identical 3 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
38. 38.🔍 Which is the odd one out? (a) compare with a limit (b) a button press (c) check if temp > 30 (d) count button presses
39. 39.⚡ A home appliance on the 230 V mains takes 5 A. What is its power (in watts)?
40. 40.🔍 Which is the odd one out? (a) a plain table fan (b) a paper calendar (c) an app-controlled bulb (d) a pencil sharpener

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